Pannarale L, Onori P, Ripani M, Gaudio E
Institute of Anatomy, State University of Rome La Sapienza, Italy.
J Anat. 1996 Jun;188 ( Pt 3)(Pt 3):693-703.
The microvasculature of the rat retina was studied in male Wistar rats in order to examine the features of the precapillary vascular pattern and structure that could affect blood flow regulation. Vascular corrosion casts and partially digested tissue specimens were observed by scanning electron microscopy. Side branching rather than bifurcation was the predominant microvascular pattern in the arterial tree. Two types of precapillary arteriole were present, one with the characteristic pattern of a preferential channel; the other gave off capillaries as terminal branches. At the origin of arteriolar side branches, smooth muscle cells appeared to buckle the endothelial nuclei into the vascular lumen. It is concluded that the rat retinal microvasculature appears to be characterised by 2 distinctive features: (1) side branching of arterioles which allows preferential flow in the most superficial layers of the retina; (2) peculiar luminal restrictions of arterioles and capillaries which permit fine regulation of blood flow.
为了研究可能影响血流调节的毛细血管前血管模式和结构特征，在雄性Wistar大鼠中对其视网膜微血管进行了研究。通过扫描电子显微镜观察血管铸型和部分消化的组织标本。侧支分支而非分叉是动脉树中的主要微血管模式。存在两种类型的毛细血管前小动脉，一种具有优先通道的特征模式；另一种以终末分支的形式发出毛细血管。在小动脉侧支的起始处，平滑肌细胞似乎将内皮细胞核挤入血管腔。得出的结论是，大鼠视网膜微血管似乎具有两个独特特征：（1）小动脉的侧支分支，其允许在视网膜最表层优先流动；（2）小动脉和毛细血管独特的管腔限制，其允许对血流进行精细调节。
